Aircraft supporting surface



' April 1, 1947. L. C. HEAL AIRCRAFT SUPPORTING SURFACE Filed Nov. 27, '1943 2 Sheets-Sheet 1 April 1, 1947. Y L. c. HEAL 2,413,301

- AIRCRAFT SUPPORTING SURFACE Filed Nov. 27, 1945 zsneets-s'neet 2 Patented Apr. 1, 1947 Lionel Charlesw Heal, :Reading, England, assignor -to1M-i-les Aircraft Limited, =acompanycf .Great Britain iipplicaltibnfloveniber 27, 1 9 13, Serial-No."511,9'9'6 in Great Britain July 24,1942

.QLCIaims.

The present invention consists in.- an aircraft supportingsurface which lmay be a main wing. or a tailplane whereof-a tip, portion is 'pivotally connected and controllable so that it can be projected into substantially vertical plane in relation to the normal attitude of theaircraft, said tip portion including anadjustable control surface operable forxcon-trol of. manoeuvre with thetip portion 1, projected into the substantially vertical plane.

Though the, inventionis considered to be particularly applicable itoatai-lless'types of aircraft in l which, of course, the wings have considerable sweep back, it is conceivable that it may .also haveuseful application to the morernormal types of aircraft including, theumain wing and tail planestructures, in whicheventrtheetipstof either ortboth the. main wing, and tailplane, may be. ad iustablein the sense intended.

Theinvention contemplatesdifferentialadjustr- I ment of the pivoted tips and/or crime control surfaces which they mount. v

In. a preferred construction .as applied .to-a taillessrmonoplane aircraft, thetwings, asis usual in such craft, have considerable sweep aback and the extreme tip: of .each wing'is pivoted abou-t an axis extendingsubstantially ,paralleltwith the longitudinal axis of the aircraft. For. take-off purposes, each wing tip is locked in ,a position in which it is in line withand forms la -continuation of the fixed wingpart and thetips, can .remain in that setting for climb ,andmordinary cruisingbecause,providing-a.contna-rotatinglairscrew, is:- employed or providing the: aircraft, is, of a multi-engine typewithoppositely rotating airscrews,.r.udder control becomes almost redundant forlall ordinary purposes while actually in flight. In preferred constructions, the trailingv edge of the pivoted wing tip is flttedlwith control surfaces, preferably in the. form of splitcfiaps operable independently of each other and preferably, also, in a: difierential sense .for employment: in the manner. of. a split flap orasaan-aileron control orzair brake, the xfixeda-inner partofthewing being providedwiththe: usual elevators. and. trailing, edge. flaps.

The. pivoted .wing ,tipsnarel adjustable. under control of .thepilotso-that they v canbe swung up. thronghapproximately 9,0 by jack. meansv or some..,other,-suitable remotely, controllable :mechanism .andlociked. in the. adjusted,.position,..the arrangement. being such. that. the adjustable. .control surfaces which .thepinotedwingtips mount remain ccntrollablefby thepilot'in the .settingin which. the wing, 'jtifpsare locked substantially 2 V vertical in relation to the wing. Thus,w-ith;the wingtips set substantially vertically relative ;to the wings, thesplit trailing edge of each wingg tip .canbe =operated independently of the-other wing tip controltooperate on one side 'of the aircraft only as a rudder, whereas, -conversely, when both splittrailing. edge flaps" of the pivoted wingtips are operated together an appreciable air-brake effect .is provided. .It isworthy. of anote that-when one split-flap-wis' operated under such conditions, a downwardcomponent-is introduced; due to theralre back of the hinge line, which arrangement. gives the equivalenteffect of aileron control. Likewise, When the split .flaps of both wing tipsareoperatedtogether, the downward component is produced onl-both sides of. theplane centre line and results in a very much increased gliding tangle.

.In operationci aircraft-iof-the tailless type, as above .set forth, the aircraft is, rudderless for take-off purposes but has elevators and flaps on the. fixed .partof the wingflas well asther-adjustable surfaces "on the adjustable .wing tips, which control. surfaces may be used asaileronsn When altitude has been achieved onshould violent manoeuvre become necessary, the tips are turned upwardly (or downwardly through an angle of approximately 90, thusuachieving. a

considerable reduction in wing area and providing the aircraft with substantial fin and rudder surfacecaftof. its centre of gravity, whichruolder surfacecan be used for .rapidflchange of. direction. and for control, purposes generally, .asherleinbeforeldescribedm I i In some cases, provision may ,be .made. for ,projectionlof. the, wing tip portions into, the sub.- stantially vertical plane."concurrently with ex. tension.- of. a retractable undercarriage in order to provide for a high degree of lateral control. and stability for landing.

{She provision: may vbe,madeior =aerodynamic balance. a of. the.- control, surfaces of the adjustable tips in, order to. keepthe eperating loadsLlow.

. order thatit may .belcl'early understood. and

readily carriedlinto effect, the invention ishereinafter described. with referencettothe v.accornpanying diagrammatic drawings, of. which;

Figure l is. a...plan.view of. a supporting surface, according to .thepresent-invention showing .Ithe

tip. portion. the extended. condition in which. it is normal with respect to the spanwisie-laxis. of. .the. surface;

Eigurejz is a rear end .elevation.corresponding togfi lll e Figure 3 is a plan view corresponding to Figure 1, but showing the wing tip projected into the substantially vertical plane;

Figure 4 is a rear end elevation corresponding to Figure 3;

Figure 5 is a side elevation corresponding to Figures 3and '4; g i a Figure. dis a fragmentary cross-section taken on the line VI-VI of Figure 4, but with control surface on the wing tip portion in the form of a split trailing edge flap opened out into an operative condition, the general outline of the control surfaces as viewed in rear end elevation in Figure 4 being indicated in Figure 4 in dotted lines.

Figure '7 is a general view illustrating one jected or normal setting, can be achieved by any a I of the common cable, hydraulic or shaft drives.

In the case of a, cable connection between the 7 surfaces 24, 25 and the pilot operated control manner of projecting the wing tip portion into 7 the vertical plane and, in this case, arrangement is made for operating the wing tip portion for projection'as the undercarriage is extended ready for' landing. a

In the drawings, the same reference numerals have been employed to indicate similar parts.

Referring now to Figures 1 and 2 of the drawings, the main part of-the supporting surface is represented by the reference numeral the wing tip portion being represented'by the reference numeral 2!, connected for pivotal movement about an axis defined by the shaft 22. The main part of the surface 20 is provided at its trailing edge with an adjustable control surface 23, which may be of any convenient or known form. At th trailing edge of the wing tip poriton 2| an adjustable control surface is provided, which preferably takes the form of a split trailing edge flap constituted by the two adjustable surfaces If we now consider Figures 3, 4 and 5, it is immediately apparent that in these figures the wing tip'portion 2| has been projected up into an angular setting in which it is disposed vertically'in relation to the normal attitude of the aircraft. As shown in Figures 3, 4 and 5, the angular setting of the wing tip portion 2| is truly vertical; in other words, it would be parallel with any normal single fixed tail fin surface embodied in the tail unit of an aircraft, but it is to be appreciated that some departure from the true vertical setting may be provided for, either in the alternative sense or in the sense for providing for some variation of the ultimate setting into which. the wing tip portion could be projected directly under control of the pilot. For instance,

the final intended setting might conceivably be vertical toth spanwise axis of the wing, in which event the upper edge of the wing tip, as seen in Figures 3, 4 and 5, would be raked somewhat inwardly, an angle corresponding to the dihedral angle of the wing. I

As seen in Figure 6, the control surfaces 24 and 25havefbeen adjusted'under control of the pilot in the'manner of a split trailing edge fiap,.in which setting they provide a wing tip air brake.

effect producingnot only a turning moment about the wing'tip axis due to the aerodynamic drag induced, but also a downward component due to a the rake back of the shaft 26 about which the surfaces 24 and 2 5 pivot in operation. In tailless types of aircraftit will be appreciated that the rakeback of awing might be appreciably greater than that of the wing form shown in Figures 1 and "3.

In regard to the operation of the control 'surfaces 23; 24 and 25, it can be said that any suitable mod of control can be provided for and ilmember, it is obvious that if the control cable is caused to pass through the axis of the shaft 22 in the course of its, run control of the surfaces will remain unaffected by the angular relationship of the wing tip portion 2| with respect to the main wing portion 20. Likewise, with a hydraulic system operating jacks extending between the wing tip portion 2| and the individual surfaces 24, 25, provision may be made for swivelling a throughflow hydraulic coupling about an axis coincident with that of the shaft 22. As a further alternative, the shaft 25 (see particularly Figures 3 and 6)' can incorporate a universal joint co-axial with respect to the shaft 22 for direct shaft control transmitting actuating loads in torque from the pilot actuated control member.

In Figure 7 there is shown one manner of projecting the wing tip upwardly into the substantially vertical setting. In this case, hydraulictension. Likewise, instead of projecting the wing tip upwardly, it might in some circumstances beprojected downwardly. In any event, where actuation of the wing tips is provided for in conjunction with undercarriage extension, the arrangement will always preferably be such that wing tip control is provided independently of undercarriage operation.

In the particular arrangement shownin Figure 7, the hydraulic jack cylinder 2,! partitioned into two axially spaced compartments by the central partition 28. piston 29 of the plunger 30 operates, whereas the plunger 3| has at its inner end the piston 32 operating in the other compartment. The plunger 30" has a connecting link 33 pivotally connected to the undercarriage leg at 34 so that axial movement of the plunger 36 results in swinging the undercarriage leg up or down about the re-, traction pivot 35 according to the sense of axial movement.

' pivoted to the outer end of the plunger 3| and to cessible to the pilot.

selector valve as to ensure'th'at actuating fluid the wing tip actuating lever 31. Three operating connections are provided to the jack cylinder the reference numerals 3B and communication with both compartments of the jack through the partition 28 Thefactuating connections 38, 39 and 40 are operable froma convenientlyavailable source of actuating pressure under control of a selector valve readily ac- If the pilot so actuates the is delivered to the jack cylinder'zl through the In one compartment the The wing tip actuatinglink 36 'is connection 39, the jack plunger 3| is retracted thereby causing the wing tip portion 2| to be set downwardly from the position in which it is shown in Figure 7. Conversely, to project the wing tip 21 into the vertical setting, as shown in Figure 7, pressure is necessarily applied and maintained by the pilot setting the selector valve to direct the actuating fluid pressure through the flow connection 49. The valving is such that when pressure is applied to the jack through the connection 39, return flow is permitted from the jack through the body of the selector valve to the hydraulic liquid supply reservoir, from which the pump or equivalent pressure member of the actuating circuit is normally fed. Likewise, when pressure is applied through the connection 40, drain of jack back to the reservoir is provided through the connection 39.

If pressure is applied-to the piston 29 of the undercarriage actuatin jack plunger 39 through the connection 49 with the connection 33 connected back to the reservoir, the undercarriage leg is extended into a position something like that shown in Figure 7. Application of pressure to the jack cylinder 2! through the connection 38 will result in undercarriage retraction. A single selector valve may be provided for actuation by the pilot to control the angular setting of the wing tip 2i and undercarriage retraction and extension entirely automatically of each other or together at the pilots choice, or the jack connections 39 and 40 may be controlled by one valve for wing tip operation and another selector valvecan, in such cases, control the connections 38 and 49. Where hydraulic operation is provided for manipulation of the valve for effective closure on completion of the requisite movement of the jack plungers 3!] and/or 3| can be utilised to provide a positive hydraulic look, but in all cases independent locking means may be provided for.

What I claim is:

1. An aircraft supportingsurface whereof a Wing tip portion is pivotally connected and controllable so that it can be projected into a substantially vertical plane in relation to the normal attitude of the aircraft, said tip portion including an adjustable control surface operable for control of manoeuvre with the tip portion projected into the substantially vertical plane.

2. An aircraft supporting surface as set forth in claim 1, wherein the adjustable control surface is subdivided into a plurality of control surfaces operable as a split trailing edge flap.

3. An aircraft supporting surface whereof a wing tip portion is pivotally connected for projection into a substantially vertical plane in relation to the normal attitude of the aircraft, an undercarriage member mounted for extension to and retraction from aircraft supporting position, single power means for simultaneously projecting said wing tip portion and extending said undercarriage member to aircraft supporting position, an adjustable control surface on the trailing edge of said wing tip portion, and means for operating said control surface with the wing tip portion projected into said substantially vertical plane.

4. An aircraft supporting surface whereof a wing tip portion is pivotally connected for projection into a substantially vertical plane in relation to the normal attitude of the aircraft, an undercarriage member mounted for extension to and retraction from aircraft supporting position, and a hydraulic jack for simultaneously projecting said wing tip portion and extending said undercarriage member to aircraft supporting position.

LIONEL CHARLES HEAL.

REFERENCES CITED The following references are of record'in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,378,387 Stokes May 17, 1921 1,947,461 De Port Feb. 20, 1934 2,173,538 McKellar Sept, 19, 1939 2,279,615 Bugatti Apr. 14, 1942 1,496,200 Baumann et al June 3, 1924 FOREIGN PATENTS Number Country Date 561,129 French July 28, 1923 347,173 Italian Mar. 20, 1937 

